Process for storing textile filaments in knitted form

ABSTRACT

A process for storing freshly extruded textile filaments for subsequent use in a textile process which comprises: spinning a fiber-forming polymer into a filament, delivering the filament to a circular one end or one-cut circular knitting machine, knitting the filament into a continuous tubular knitted article, delivering this knitted article into a storage container and cutting the knitted article when the container is full.

' nited States Paten Corbiere Nov. 26, 1974 [54] PROCESS FOR STORING TEXTILE 3,333,441 8/1967 Sousshoff 66/147 FILAMENTS IN KNITTED FORM 3,529,447 9/1970 Fleissner et 211.. 28/7216 UX 3,542,309 11/1970 Willis et al 1 66/125 A UX entor: Claude Corb1ere, V1llaLe Regal 3,611,701 10 1971 Scherzberg .1 28/7216 x 42, Riorges, France 3,720,984 3/1973 Roberson, Jr 28/72.16

[22] Filed: Nov. 28, 1972 I OTHER PUBLICATIONS [21] APPL 309 9 3 Some Conventional and Uncoventional Methods and Processes in Double Jersey, by F. Strasser, Textile lnstitute and Industry, Vol. 8, No. 12, December, 1970, [30] Foreign Application Priority Data 7 Novf29, 1971 France 71.42787 Primary ExaminerRobert R. Mackey [52] U.S. CI 28/72.16, 66/125 A, 264/103 Attorney, Agent, or Firm--Sherman & Shalloway [51] Int. Cl D04 b l9/00 v [58] Field of Search 66/125 A, 125 R, 147; 57 ABSTRACT 28/7216; 264/103; 26/55 R A process for storing freshly extruded textile filaments for subsequent use in a textile process which com- [56] References cued prises: spinning a fiber-forming polymer into a fila- UNITED STATES PATENTS ment, delivering the filament to a circular one end or 1,524,388 1/1925 one-cut circular knitting machine, knitting the filalt7671762 6/1930 ment into a continuous tubular knitted article, delivering this knitted article into a storage container and 21826Z1 67 3/1958 cutting the knitted article when the contamer is full. 3,248,904 5/1966 Frishman 66/147 6 Claims, 4 Drawing Figures PROCESS FOR STORING TEXTILE FILAMENTS IN KNITTED FORM BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a process for storing textile yarns. More particularly, this invention relates to a process for storing freshly extruded thermoplastic textile filaments in a knitted form.

2. Description of the Prior Art Synthetic filament spinning machines, i.e., spinnerets, produce monoand multi-filament textile materials continuously while textile machines which utilize completely processed, i.e., drawn, stretched and twisted yarns, often work in a discontinuous manner since the supply to these machines is in the form of discreet packages, such as bobbins of textile yarn or filaments.

One conventional way of storing freshly extruded filaments is to form a spin-package on a normally cylindrical tube. However, the amount of yarn which can be placed on each individual spin-package is limited due to various machine limitations, both with regard to size and speed. Also, automatic transfer systems which substitute empty bobbins for full bobbins do so with a minimum of waste; however, even with waste yarn being at a minimum, a significant amount of material is consumed in the so-called waste material. Furthermore, these automatic machines are quite large, complex and costly to run. In addition to the cost of the machines which transfer one empty tube for a full tube, the tubes themselves are expensive to produce even if the same are utilized repeatedly, since in order to obtain a desired winding structure on the tubes, the tubes must be very wellbalanced and made to exact specifications.

Also, the formation of a so-called tail, i.e., that portion of the spin-package which enables the package to be connected to the end of the package succeeding it (in the creel) is a very expensive operation and often subjects the freshly extruded yarns to stresses which tend to spoil the same making'them useless as textile materials.

In order to obviate the deficiencies of the spinpackage storing system, it has also been proposed to utilize textile storing packages not utilizing a support,

called cheeses, by introducing the yarns into a centrifugal pot revolving at high speed. However, this method, although dispensing with the requirement of winding tubes or bobbins, has a number of inherent deficiencies which have precluded its widespread utilization. Namely, these deficiencies are limited weight of yarn in each package, uneven tension of the yarn, the difficulty in finding the ends of the package so that the same may be attached to other similar packages for textile processing and the relatively fragile nature of the packages or cheeses themselves.

'A still further method of storing freshly extruded yarns comprises extruding these yarns directly into storage containers having a generally large size which revolve slowly. These filaments are projected into the pot and form layers in a coil so that the same may be withdrawn at a later time. However, this method, although very satisfactory when heavy tows of wet filaments are to be utilized and drawn into staple fiber, is virtually useless for delicate monoand multi-filaments of textile and even industrial yarns, i.e., those havinga count lower than 5,000 Dtex. Furthermore, when the yarns have a count lower than 10,000 Dtex, it is difficult to form the helical layers in the pot and it is still more difficult to get the fibers out of the pot or container without damage if the withdrawal speed is high and the yarn count is low. Accordingly, although this method allows easy tailing, it is only suitable for use in producing undrawn tows for staple fiber.

Each of the storage means discussed above has a number of disadvantages, such as relatively compact masses or unevenly formed spin-packages. Changes in temperature, relative humidity and other environmental changes do not penetrate these packages completely and an uneven filament is produced due to such changes in temperature and humidity since only those filaments at the top and sides of the package are affected. Since freshly spun mono-filments and multifilaments must often be aged before they can be utilized, this uneven contact with the atmosphere creates uneven physical properties along the length of the filaments.

The most common storage method for freshly ex truded synthetic filaments is the winding of these filaments on a cylindrical or conical tube. Although the formation of these spin-packages on a tube is a widely practiced storage method, there are a number of problems connected with the mere formation of such a package, such as proper crossing angle, shape of the generating lines, fraying or splitting of the filaments, but more importantly, during the formation of these spin-packages, the yarns must change directions by being guided through a-thread guide. These changes of directions cause an uneven drawing of the freshly extruded filaments, which creates structural differences eventually leading to unacceptable filaments which have varying dye affinity and structural properties, subsequent to drawing. Furthermore, since the layers of filaments are wound over each other, this aggravates the difference in structure along the length of the filaments. The outer layers block progressively the under layers. This leads to differences of structure along the filaments, aggravated by the storage duration. Such differences can lead after drawing to problems of dye affinity, according to the various local pressures exerted along each undrawn stored filament.

This happens for example, when the undrawn filaments shrink on the bobbin. They can contract so strongly as to crush a weak tube. Of course, when this happens, the entire batch of yarn or spin-package has become useless.

Also, the opposite effect is a problem, namely, since the filaments are spun and quickly wound into a spinpackage, the inner layers during winding regain or absorb some water from the atmosphere and elongate, thereby softening the whole package, making winding virtually impossible, with unwinding causing tangles and other unacceptable feed properties.

In the past, in order to alleviate these various problems caused by winding or storing undrawn, freshly extruded filaments immediately upon extrusion, these filaments were subjected to a stabilization process which was designed to allow the yarns to become sufficiently stabilized before the same were wound into spinpackages. Although conventional spin-packages may be utilized, using such an additional processing step, this operation or process step is quite costly and additionally, is relatively slow thereby limiting production speed.

BRIEF DESCRIPTION OF THE INVENTION It is within the above environment and background that the process of the present invention was developed. Briefly, the process of the present invention which is directed toward storing freshly extruded filaments without the necessity of any additional stabilization treatment, comprises spinning a fiber-forming polymer into filaments, immediately delivering these filaments to a circular one-end circular knitting machine, knitting these filaments into a continuous tubular non-revolving knitted article, delivering the knitted article into a storage container and cutting the knitted article when the container is full. By way of the foregoing process, freshly spun, monoand multi-filment yarns may. be produced and stored in a neat and orderly manner while the filaments themselves may be properly and uniformly aged.

OBJECTS AND ADVANTAGES It is therefore the primary object of the present invention to provide a process for quickly and efficiently storing freshly spun, synthetic yarns so that the same may be uniformly stored and aged.

It is a further object of the present invention to provide a process for the storing of freshly extruded textile yams wherein during the storing, the yarns are not subjected to stresses or tension.

It is a still further object of the present invention to provide a process for storing freshly extruded, synthetic filaments wherein the filaments are knitted into a tubular article immediately upon extrusion into filaments and stored in a container until further use.

It is a still further object of the present invention to provide a process for storing freshly extruded textile filaments wherein the textile filaments may be stored and delivered without the necessity of expensive and wasteful automatic transfer systems.

Still further objects and advantages of the process of the present invention will become more apparent from the following more detailed description thereof.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic illustration showing how filaments produced by a spinnerette are directed into the knitting head of a one-end or a one-cut knitting machine and knitted into a tubular structure which is then directed to and laid up in a container;

FIG. 2 is a schematicillustration showing how the knitted tubular structure is cut for storage in an individual package;

FIG. 3 is a schematic illustration showing a length of yarn deknitted from one tubular structure knotted to a length of yarn deknitted from another tubular structure and showing'how the yarn is deknitted by pulling the yarn through a yarn guide; and

FIG. 4 if a schematic illustration showing a length of yarn composed of a plurality of filaments being drawn and then separated with each of the filaments being wound on a separate bobbin.

DETAILED DESCRIPTION OF THE INVENTION The foregoing objects and advantages are achieved through the process of the present invention which comprises spinning a fiber-forming polymer into a filament, immediately delivering the filament to a circular, one-end fixed head (i.e., non-rotative) knitting machine, knitting the filament into a continuous, tubular, knitted article, delivering the knitted article without twist into a storage container and cutting the knitted article when the container is full.

By a one-end fixed head knitting machine is meant a machine which is exclusively fed with and which works with only one yarn per knitting head. The yarn may be either a mono-filament yarn or a multi-filament yarn and is delivered along the axis of the knitting machine around which it rotates to form a spiral producing a tubular fabric which is formed by knitting loops of the yarn. In this type of knitting machine, the knitting needles do not rotate about the axis of the machine. Consequently, the tubular fabric produced does not rotate.

Although the storage of drawn yarns in the knitted form is known, the process of the present invention wherein freshly extruded undrawn yarns and filaments are delivered directly from the spinning nozzle to the knitting machine results in a simple and expeditious method for storing freshly extruded unaged and undrawn synthetic multiand mono-filaments themselves will be uniformly stabilized without localized stresses forming in the package. Furthermore, since the basic storage package is completely unsupported and flexible any change in size of the yarns does not produce entanglement of the yarn package, in effect destroying the same.

In accordance with the process of the present invention, any synthetic monoor multi-filament having any particular corss-section, either circular or lobal or any other desired filament cross-section, may be spun utilizing a conventional spinneret and utilizing either a wet spinning or a dry or melt spinning process. The filaments are then taken directly from the output of the spinneret or spinning device and directly delivered to a circular knitting machine.

Between the spinning and the knitting process steps, it is often desirable to treat the freshly spun yarn with a lubricant, such as by passing the yarns over a lubricant contact device, such as a coated roller, without applying any tension or drawing to the freshly spun filaments. The application of a conventional lubricant, which may be any conventional lubricant or sizing agent employed in the textile industry for the particular synthetic yarn being produced, aids in producing an even knit in the cylindrical knitted article.

These freshly extruded monoand multi-filaments are then, subsequent to the optional lubricating step, directed to the input of a circular one-end, fixed-head, knitting machine. These filaments are delivered to the knitting head by passing along the axis of the cylindrical knitted article and distributed around the knitted circular knitting head under constant tension by a revolving supply element, rotating around the axis of the knitting head. These filaments are then knitted under constant tension into the tubular knitted article which is then directly delivered from the knitting head to a supply or storage container. The speed at which the knitting machine or knitting process step is conducted is preferably approximately equal to the spinning speed for these synthetic monoand multi-filament yarns. Although the knitting head itself is operating at high speed, due to the fact that the yarns are knitted into a knitted tubular article, the speed of the knitted article coming from the knitting machine is considerably reduced, thereby allowing an operator sufficient time to substitute empty storage canisters for the storage canisters which have become full. 4

By utilizing the process of the present invention, the freshly extruded filaments are uniformly subjected to stabilization, aging and tension, both during the formation of'the knitted article and during subsequent treatments which may include washing, sizing, dyeing, etc. Further, although a slight twist is imparted to the yarns upon knitting, utilizing the circular fixed head knitting machine, this twist is reversed or taken out when the articles are subsequently deknitted for use. Furthermore, due to the speed of the output of the knitting machine, the operator can easily locate the starting or tail strand for the storage article so that the same may be easily connected to the preceding and following storage packages in use.

Although any conventional storage canister may be utilized, it is preferred to utilize a disposable storage canister having a plastic film lining which can be sealed immediately after filling, thereby assuring the filaments will be subjected to constant humidity and temperature conditions during storage and transportation. The storage package of the present invention is subsequently used as supply for other textile apparatus simply by taking the leading tail end of the yarn and deknitting the entire tubular package.

Synthetic filaments which may be produced in accordance with the process of the present invention include any conventional filaments generally utilized in the textile industry, including polyethylene terephthalate,

.polyhexamethylene adipamide, poly-e-caprolactam,

polyacrylonitrile, cellulose acetate, copolymers of acrylonitrile, copolymers of polyethylene terephthalate,

etc.

DETAILED DESCRIPTION OF THE DRAWINGS Referring now to FIG. 1, there is shown a spinnerette 10 which produces a'plurality of filaments 11-11 that are converged by a guide 12 to form a strand of yarn 13. The yarn 13 is lubricated by an oiling station 14 and is advanced by a yarn pull system 16 into-a second convergence guide 17. From the second convergence guide 17, the yarn strand 13 enters the knitting head 18 of a-one-end, or rather one-cut, knitting machine 19 through an opening 21. As the head 18 receives the yarn 13, it rotates in thedirection of the arrow 22 to distribute the yarn on knitting needles (not shown). As

the yarn is distributed on the needles, the needles recip rocate vertically, as shown by the arrow 23, to produce a tubular structure 24 which exits from the bottom of the knitting machine.

, 'As the tubular structure 24 exits from the bottom of the knitting machine, it is pulled by a pair of rollers 26-26 and directed into a chute 27 which reciprocates back and forth to deposit the tubular structure in a flexible bag or the like 29. The flexible bag 29 is removably retained in a rigid container 31 and may be closed at the top, as shown in FIG. 2, for subsequent transport, storage or processig of the tubular knitted article 24.

As seen in FIG. 2, the tubular knitted article 24 may As schematically illustrated by nozzle 30 in FIG. 2, the yarn 13 composing the knitted fabric 24 may be treated while in tubular form as it is stored. This treatment may include such conventional processes as washing, dyeing, sizing or the application of finishing agents. It should be kept in mind that although the treatment is shown being applied to the tubular fabric 24 while the fabric 24 is in the container 31, the treatment may also be applied at any time while the yarn 13 is in the tubular form.

Referring now to FIG. 3, it is seen how the tubular structure 24 is deknitted by pulling the strand of yarn 13 therefrom through a yarn guide 32. In order to continuously produce a strand of yarn 13, the tubular structure 24 of one package or bundle is knotted together, as shown by knot 33, with an adjacent tubular structure, so that as one package is deknitted, subsequent packages are available for immediate deknitting.

Referring now to FIG. 4, there is shown a strand of yarn 13 which is composed of a plurality of filaments, 11a, 11b, 11c, 11d, and 11e This plurality of filaments 11a-11e was converged by the guide 12 in FIG. 1 to form the strand of yarn 13 which was then knitted into the fabric 24 by the one-end or one-cut knitting machine, as seen in FIG. 1. The strand of yarn 13 has a zero twist and is the same strand of yarn as that being pulled from the storage container 31 of FIG. 3. The strand of yarn 13 is then drawn in a conventional manner between a pair of conventional drawing rollers 41 and 42 or the like. The drawing roller 42 moves at a higher speed than the drawing roller 41 so that the yarn strand 13 which includes the filaments 11a-1le is drawn.

In order to provide for smooth drawing of the yarn 13, a conventional drawing rod 43 is disposed at an acute angle to the yarn 13 and receives the yarn l3 therearound. The importance of having a zero twist in the yarn 13 occurs as the yarn 13 is looped around the drawing rod 43. If the yarn 13 were twisted, then it would be subject to uneven drawing as the twist in the yarn accumulates and releases above the rod 43 while the yarn passes over the rod 43. By having a zero twist, the filaments lla-lle are parallel to one another and the yarn strand passes smoothly over the rod 43 as it is drawn. Since the filaments lla-lle are parallel, they can be separated continuously and wound simulta neously onto the separate bobbins 44a-44e in parallel.

The process of the present invention will now be illustrated by way of the following illustrative examples, wherein all parts and percentages are by weight and all temperatures are in degrees Centigrade.

EXAMPLE 1 A polyhexamethylene adipamide multi filament yarn is extruded under conventional extruding conditions to truded thereby avoiding any undue tension or uneven tension in the formation and storage of the yarn. Furthermore, the slow progress or linear speed of the jersey as it exits from the knitting machine, allows the freshly extruded filaments to be properly conditioned and regain humidity.

Furthermore, this slow jersey linear speed allows the container to be easily changed since the operator cuts the jersey and arranges the tubular article in the container so that the loose ends, i.e., tails, on both ends are easily accessible, and may be knotted with other similar storage packages for use as a supply to a textile process. This package is then removed and closed and enclosed in a non-returnable, light, throw-away package for storage and possible transportation thereby avoiding any possible transportation injury to the filament. In the creel of a drawing machine, this jersey is deknitted under low and constant tension, merely pulling out the undrawn yarn. Furthermore, the slight twist, i.e., one turn per turn of the revolving supply unit, which is given to the yarn during knitting and facilitating the knitting is cancelled by the deknitting, thereby producing a finally drawn yarn having remarkable quality with very uniform physical properties, and dye affinity and without any broken ends or other fraying.

EXAMPLE 2 EXAMPLE 3 AND COMPARATIVE EXAMPLE I Utilizing the procedure of Example I with a polyhexamethylene adipamide yarn having a count of 100/10 Dtex these yarns are stored by knitting according to the process of the present invention and by winding on a tube.

The yarn which is wound on a tube reacts as a spring when it is unwound, causing variations in the tension on the yarn. Furthermore, the filaments become intermingled and catch on the thread guides, thereby causing numerous defects and frayed, broken ends.

The same yarn, however, when stored in accordance with the process of the present invention, permits uniform conditioning during storage and produces a uniform yarn upon drawing.

EXAMPLE 4 AND COMPARATIVE EXAMPLE 2 Two separate multi filament polyester yarns are extruded under similar conventional operating conditions in order to obtain yarns subsequent to drawing of 167/30 Dtex. The control filaments are wound onto a standard bobbin, the other filaments are knitted in accordance with the procedure of Example 1. Both the bobbin package and the jersey or knitted package are stored for 48 hours and then fed into a draw-texturing machine. In comparison, the drawn yarn which was stored as a knitted jersey runs considerably more smoothly and shows less nipped or frayed parts. FUrthermore, an elongation-strength dynamometric curve shows that the physical properties of the polyester yarn stored as a knitted jersey is considerably more regular than that of the similar yarn stored on a conventional bobbin. Furthermore, the dye affinity of the yarn stored as a jersey, is considerably more regular and uniform than the dye affinity of a similar yarn stored on a bobbin.

EXAMPLE 5 Utilizing the procedure of Example I, subsequent to knitting and storage, the knitted tubular aritcle is dyed before deknitting. When this tubular article is deknitted in the creel of a drawing machine, the finally produced drawn yarn has excellent color characteristics and physical properties.

EXAMPLE 6 The process of Example I is repeated with the exception that five filaments having a count of 12 Dtex each are knitted simultaneously to form a knitted tubular article. These five individual mono-filaments are then deknitted and drawn in a similar manner, but rewound for final storage individually, producing five separate storage bobbins of mono-filaments. The physical properties and dye affinity of each of these mono-filaments are quite excellent and uniform.

EXAMPLE 7 The process of Example 1 is again repeated with the exception that a poly-e-caprolactam yarn is produced to obtain a drawn yarn having a count of /35 Dtex. The knitted tubular article is washed and sized before deknitting in the drawing creel. These filaments produced have excellent physical properties, the same being quite uniform.

While the process of the present invention has been illustrated by way of the foregoing specification and illustrative examples, the same are to be in no way limiting the process of the present invention which is properly defined by way of the following appended claims.

What is claimed is:

1. A process for manufacturing textile filaments from a polymer comprising the steps of:

spinning the polymer into a filament yarn;

delivering the filament yarn to a circular one-cut knitting machine immediately after spinning; knitting the filament yarn into a continuous nonrotating tubular structure;

advancing the knitted structure into a storage container;

cutting the knitted structure after a pre-determined amount of structure has accumulated;

stabilizing the filament yarn in the knitted structure while the knitted structure is in the storage container by atmospherically aging the knitted structure; and then deknitting the filament yarn accumulated in the knitted structure to remove the slight twist imparted to the filament yarn during knitting of thee filament yarn, thus producing zero twist yarn for further processing.

2. The process of claim 1, wherein the knitted structure is washed subsequent to advancing the knitted structure into the storage container and prior to deknitting the knitted structure.

3. The process of claim 1, wherein the knitted structure is sized subsequent to advancing the knitted strucconsists of a plurality of strands.

6. The process of claim 5, wherein the filament yarn is drawn after deknitting and wherein each strand of the filament is thereafter wound on a separate bobbin.

l l l 

1. A process for manufacturing textile filaments from a polymer comprising the steps of: spinning the polymer into a filament yarn; delivering the filament yarn to a circular one-cut knitting machine immediately after spinning; knitting the filament yarn into a continuous nonrotating tubular structure; advancing the knitted structure into a storage container; cutting the knitted structure after a pre-determined amount of structure has accumulated; stabilizing the filament yarn in the knitted structure while the knitted structure is in the storage container by atmospherically aging the knitted structure; and then deknitting the filament yarn accumulated in the knitted structure to remove the slight twist imparted to the filament yarn during knitting of the filament yarn, thus producing zero twist yarn for further processing.
 2. The process of claim 1, wherein the knitted structure is washed subsequent to advancing the knitted structure into the storage container and prior to deknitting the knitted structure.
 3. The process of claim 1, wherein the knitted structure is sized subsequent to advancing the knitted structure into the storage container and prior to deknitting the knitted structure.
 4. The process of claim 1, wherein the filament yarn is produced from the polymer by melt spinning the polymer.
 5. The process of claim 1, wherein the filament yarn consists of a plurality of strands.
 6. The process of claim 5, wherein the filament yarn is drawn after deknitting and wherein each strand of the filament is thereafter wound on a separate bobbin. 